Linux Mode in the Dell Latitude line offers the user a minimal environment where one can surf the web, check email, and perform a few other tasks. In this mode that boots in 2 seconds, the battery lasts about 19 hours.
What's the magic that makes this happen, you ask? An ARM embedded processor and a special version of Linux designed specifically for the ARM. From the ARM website:
ARM is the industry's leading provider of 32-bit embedded RISC microprocessors, offering a wide range of processors based on a common architecture and delivering high performance together with low power consumption and system cost.
ARM processors are licensed by the majority of the world's leading semiconductor manufacturers, who together have shipped in excess of ten billion processors since the company was formed in 1990.
This combination of an ARM processor, Linux, and long battery life turn a clunky laptop with a battery life of 1 to 2 hours into a flexible and portable Internet gadget. You won't even have to carry around the AC adaptor in Linux mode. Just grab the laptop and go in search of a free WiFi connection at your local coffee shop.
Manufacturers and VARs (Value Added Resellers) know that Linux is the key to low-cost, low power consumption, and low requirement computing. It may never dominate the Desktop market completely but it will dominate the Internet-based applications arena.